Specify deps via setup.py arguments.

setup.py

@@ -1,17 +1,39 @@
 import os
+import sys
 from distutils.core import setup, Extension
 
-use_zlib = True  # TODO Configurable somehow?
+# --with-zlib: use zlib for compressing and decompressing
+# --without-zlib: ^ negated
+# --with-zlib=<dir>: path to zlib if needed
+# --with-libmemcached=<dir>: path to libmemcached package if needed
 
+use_zlib = True
+pkgdirs = []  # incdirs and libdirs get these
 libs = ["memcached"]
 defs = []
 incdirs = []
 libdirs = []
 
-if "LIBMEMCACHED_DIR" in os.environ:
-    libdir = os.path.normpath(os.environ["LIBMEMCACHED_DIR"])
-    incdirs.append(os.path.join(libdir, "include"))
-    libdirs.append(os.path.join(libdir, "lib"))
+# Hack up sys.argv, yay
+unprocessed = []
+for arg in sys.argv[1:]:
+    if arg == "--with-zlib":
+        use_zlib = True
+        continue
+    elif arg == "--without-zlib":
+        use_zlib = False
+        continue
+    elif "=" in arg:
+        if arg.startswith("--with-libmemcached=") or \
+           arg.startswith("--with-zlib="):
+            pkgdirs.append(arg.split("=", 1)[1])
+            continue
+    unprocessed.append(arg)
+sys.argv[1:] = unprocessed
+
+for pkgdir in pkgdirs:
+    incdirs.append(os.path.join(pkgdir, "include"))
+    libdirs.append(os.path.join(pkgdir, "lib"))
 
 if use_zlib:
     libs.append("z")